The present invention relates to foods and food ingredients containing digestible carbohydrates.
In 1985, the World Health Organization (WHO) estimated 30 million people worldwide had diabetes. By 1995, this number increased to 135 million. The estimated number rose again in 2000 to 177 million. This number is expected to reach 370 million by 2030. In 2000, seventeen million Americans were estimated to be diabetic. Diabetes in adults is now a global health problem. Populations of developing countries, minority groups, and disadvantaged communities in industrialized countries face the greatest risk.
The worldwide incidence of obesity, as defined by WHO, has soared from 12% to 18% in just the last seven years. Statistically, one in five of the world's population is obese. The US is presently the “fat capital”, with more than 64% of the adult population being overweight. Results from the US 1999-2000 National Health and Nutrition Examination Survey (NHANES), indicate that an estimated 15 percent of children and adolescents (ages 6-19 years) are overweight.
Being either diabetic or overweight substantially raises the risk of mortality from hypertension, dyslipidemia, type 2 diabetes, coronary heart disease, stroke, gallbladder disease, osteoarthritis, sleep apnea, respiratory problems, and endometrial, breast, prostate, and colon cancers. In 2002, the estimated US healthcare costs attributed directly to the treatment of obesity and diabetes were approximately $200 billion annually.
A common factor related to these diseases is a malfunction in the metabolism of digestible carbohydrates. This malfunction causes abnormal levels of blood glucose and insulin. Insulin promotes the production and storage of fat. High average levels of glucose (>180 mg/dl) in the blood stream will bind to organ proteins (glycosylation) resulting in the deterioration of organ function. A measure of glycosylation is the HbA1c blood test that defines the extent to which glucose is bound to hemoglobin. This measurement estimates the average level of glucose in the blood stream over the 3-month period prior to the test. HbA1c test results higher than 8.0% (>180 mg blood glucose/dl) are an indicator of increased potential for organ damage that includes serious eye, cardiovascular, circulatory, kidney, and nerve diseases.
It is important for diabetics and those that are overweight or obese, to avoid foods with a high glycemic response, i.e. those that result in abnormally high levels of blood glucose soon after ingestion. Instead, diabetics and those controlling their weight require foods having a relatively low blood glucose response (glycemic response or index), which results in a slower rate of glucose release into the blood. Slowing the rate of release of glucose into the blood reduces the risk of both high blood glucose (hyperglycemia) and low blood glucose (hypoglycemia). It has been suggested that significant health advantages can be achieved if 2 hr postprandial (after a meal) blood glucose levels can be maintained as close to normal as possible (140 mg/dl). A problem in meeting this goal is experienced when large quantities of foods high in digestible carbohydrates are consumed. Such foods typically include bakery products, pastas, rice, snacks, potatoes, sauces, gravies, beverages, soups, casseroles and candies. These foods, containing high levels of digestible starch and/or sugars, especially when eaten in excess can significantly increase 2 hr postprandial blood glucose levels.
Appetite suppression is another reason for maintaining normal 2 hr postprandial blood glucose levels.
Herein lie the importance and the need to reduce blood glucose responses resulting from the consumption of popular foods containing high levels of digestible carbohydrates. Although there is no official definition of “high levels of digestible carbohydrates”, the Food and Nutrition Board under the National Academies of Sciences' Institute of Medicine has set a Recommended Daily Allowance (RDA) for Total Digestible Carbohydrate for children and adults to be 130 g/day. It is apparent how this RDA is easily being surpassed by a large majority of the population when consuming their typical diets.
Diabetes is a malfunction in the metabolism of digestible carbohydrates caused by the body's inability to adequately produce or efficiently utilize insulin. Insulin is needed to facilitate the transport of blood glucose into cells where it is converted to energy. Failure to transport glucose into cells results in elevated blood glucose levels (normal fasting blood glucose levels are between 70 and 100 mg/dl). There are two types of diabetic conditions: juvenile-onset diabetes (Type I) and the mature-onset diabetes (Type II). In Type I diabetes, the body does not produce insulin. The administration of insulin is necessary to lower blood glucose to normal levels. In Type II diabetes, either the body doesn't produce enough insulin or cells lose their ability to efficiently use insulin (insulin resistance) to facilitate the transport of glucose into cells.
Obesity is also a malfunction in the metabolism of digestible carbohydrates. High levels of blood insulin can result from self-administration or as a result of insulin resistance. When insulin resistance occurs, glucose levels rise signaling for the production of additional insulin. Thus blood insulin levels become excessive. In addition to insulin's role in regulating glucose metabolism, insulin stimulates the synthesis of fats (lipogenesis) and diminishes the breakdown (lipolysis) and conversion of fat to energy. Thus high levels of insulin increase fat production and storage causing conditions of overweight and obesity.
A primary approach for reducing blood glucose levels and related insulin levels is the strict adherence to a diet that minimizes postprandial glucose response. However, compliance to a diet that results in normal blood glucose levels is difficult since the majority of foods consumed daily in a typical diet have high levels of digestible carbohydrates. Consequently, food products and dietary management systems are needed to help control and maintain blood glucose levels to as close to normal as possible, in order to reduce the incidence and complications of diabetes. More specifically, there is a need for low digestible carbohydrate versions of highly consumed, conventional, starchy, sugary, food products.
It can be concluded that being overweight or having diabetes poses a major public health challenge. These diseases are epidemic and represent leading causes of death worldwide. They also are primarily caused by malfunction in the metabolism of digestible carbohydrates. Reducing the digestion and absorption of digestible carbohydrates in the small intestine can 1) help promote weight loss and control, 2) help reduce the incidence of Type II diabetes, 3) reduce the morbidity and mortality resulting from diabetes and conditions of obesity, 4) promote better health, and 5) reduce healthcare costs.
It is common art to produce foods containing low levels of digestible carbohydrates by diluting their levels in foods with food ingredients that are not glycemic (do not produce a blood glucose response). Typically foods with high levels of digestible carbohydrate are diluted with proteins, dietary fibers, fats, and resistant starches. The dilution approach to producing low glycemic foods has several disadvantages: 1) the cost of the digestion-resistant carbohydrate material is usually significantly more expensive due to replacing low cost digestible carbohydrates with ingredients that are typically 5 to 15 times more expensive, 2) the low digestible carbohydrate foods usually don't have the same consumer acceptance as foods with higher levels of digestible carbohydrates and 3) compliance to a diet utilizing non-standard foods can be difficult due to poor organoleptic quality, limited availability of low carbohydrate foods needed to provide adequate nutrition as well as necessary eating enjoyment.